Module Use and Impact The Morphology and Imaging Module has two primary functions. First, it processes ocular and brain tissues for microscopy. This is a particularly valuable service for the physiologists and molecular biologists that do not have experience in histological techniques, but are very interested in imaging the tissues and cells that express genes or gene products they are investigating. Tissues are routinely processed for immunocytochemistry and in situ hybridization. Mr. Gillett devised a technique for plastic imbedding zebrafish embryos so the eyes would be stabilized and could be sectioned in the correct orientation. Second, this Module provides expertise for and access to equipment used for tissue processing, microscopy, and image analysis. An additional function of this Module is to provide training in the use of Module microscope and imaging equipment, tissue processing, in situ hybridization, immunohistological techniques, and image analysis software to participating investigators and their staff when requested. The Module will also assist with the planning and execution of immunohistochemistry experiments for investigators who lack the necessary expertise.